CodeForces--621A--Wet Shark and Odd and Even(数学水题)

Time Limit: 2000MS   Memory Limit: 262144KB   64bit IO Format: %I64d & %I64u

Status

Description

Today, Wet Shark is given n integers. Using any of these integers no more than once, Wet Shark wants to get maximum possible even (divisible by 2) sum. Please, calculate this value for Wet Shark.

Note, that if Wet Shark uses no integers from the n integers, the sum is an even integer 0.

Input

The first line of the input contains one integer, n (1 ≤ n ≤ 100 000). The next line contains n space separated integers given to Wet Shark. Each of these integers is in range from 1 to 109, inclusive.

Output

Print the maximum possible even sum that can be obtained if we use some of the given integers.

Sample Input

Input
3
1 2 3
Output
6
Input
5
999999999 999999999 999999999 999999999 999999999
Output
3999999996

Hint

In the first sample, we can simply take all three integers for a total sum of 6.

In the second sample Wet Shark should take any four out of five integers 999 999 999.

Source

Codeforces Round #341 (Div. 2)

给出n个数,任取若干个数,得到最大偶数和
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
long long a[1000000];
int main()
{
	int n;
	scanf("%d",&n);
	long long sum=0,b;
	int l=0;
	for(int i=0;i<n;i++)
	{
		scanf("%lld",&b);
		if(b%2)
		{
			a[l++]=b;
			sum+=b;
		}
		else
		sum+=b;
	}
	sort(a,a+l);
	if(sum%2) printf("%lld
",sum-a[0]);
	else printf("%lld
",sum);
	return 0;
}


原文地址:https://www.cnblogs.com/playboy307/p/5273483.html